Two-loop N $$ \mathcal{N} $$ = 2 SQCD amplitudes with external matter from iterated cuts

Abstract We develop an iterative method for constructing four-dimensional generalized unitarity cuts in N $$ \mathcal{N} $$ = 2 supersymmetric Yang-Mills (SYM) theory coupled to fundamental matter hypermultiplets ( N $$ \mathcal{N} $$ = 2 SQCD). For iterated two-particle cuts, specifically those inv...

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Bibliographic Details
Main Authors: Gregor Kälin, Gustav Mogull, Alexander Ochirov
Format: Article
Language:English
Published: SpringerOpen 2019-07-01
Series:Journal of High Energy Physics
Subjects:
Online Access:http://link.springer.com/article/10.1007/JHEP07(2019)120
Description
Summary:Abstract We develop an iterative method for constructing four-dimensional generalized unitarity cuts in N $$ \mathcal{N} $$ = 2 supersymmetric Yang-Mills (SYM) theory coupled to fundamental matter hypermultiplets ( N $$ \mathcal{N} $$ = 2 SQCD). For iterated two-particle cuts, specifically those involving only four-point amplitudes, this implies simple diagrammatic rules for assembling the cuts to any loop order, reminiscent of the rung rule in N $$ \mathcal{N} $$ = 4 SYM. By identifying physical poles, the construction simplifies the task of extracting complete integrands. In combination with the duality between color and kinematics we construct all four-point massless MHV-sector scattering amplitudes up to two loops in N $$ \mathcal{N} $$ = 2 SQCD, including those with matter on external legs. Our results reveal chiral infrared-finite integrands closely related to those found using loop-level BCFW recursion. The integrands are valid in D ≤ 6 dimensions with external states in a four-dimensional subspace; the upper bound is dictated by our use of six-dimensional chiral N = (1, 0) SYM as a means of dimensionally regulating loop integrals.
ISSN:1029-8479